To the Editor.—
I have recently observed a particularly effective way to evaluate CSF visually for the presence of xanthochromia. The usual procedure consists of centrifugation of bloody CSF, followed by placing the container of fluid next to a white object (usually a lab coat) or holding it up to a light source. The supernatant is then inspected for xanthochromia, sometimes compared with water in a similar container. I have found that a more effective approach is holding the CSF container next to an x-ray view box. Thus, an easily accessible, brightened white background makes xanthochromia easier to spot. I have found this to be more effective than the traditional techniques for identifying faint xanthochromia.